* {
    margin: 0;
    padding: 0;
}

a {
    outline: none;
    text-align: end;
    text-decoration: none;
    font-size: 18px;
    color: rgba(255,255,255,0.9);
}
body {
    height: 100vh;
    background: url(../image/bg.jpg) no-repeat;
    background-size: cover;
    display: flex;
    justify-content: center;
    align-items: center;
}
.box{
    width:1200px ;
    height:800px ;
    background-color: aliceblue;
    display: flex;
}
.box-left{
    width: 300px;
    height: 800px;
}
*{
    /* 初始化 */
    margin: 0;
    padding: 0;
}
body{
    /* 100%窗口高度 */
    height: 100vh;
    /* 弹性布局 居中 */
    display: flex;
    justify-content: center;
    align-items: center;
    background-color: #e2c8db;
}
ul{
    list-style: none;
}
nav{
    /* 固定定位 */
    position: fixed;
    width: 300px;
    height: 800px;
 background-image: url("../image/1.jpg");
    background-size:cover;
}
.menus{
    margin: 50px 0;
    color: #fff;
}
.li{
    letter-spacing: 2px;
    font-size: 17px;
    font-weight: 600;
    padding: 16px 0;
    /* 动画过渡 */
    transition: 0.3s;
}
.menus li:hover{
    background-image: url("../image/2.jpg");
    background-size: cover;
}
.li .fa{
    font-size: 20px;
    width: 50px;
    height: 20px;
    text-align: center;
    margin-left: 5px;
}
.li ul{
    width: 0;
    height: 550px;
    padding: 50px 0;
    background-image: url("../image/2.jpg");
    background-size: cover;
    position: absolute;
    top: 0;
    right: 0;
    overflow: hidden;
    transition: 0.3s;
}
.li ul li{
    padding: 16px 24px;
    /* 文字禁止换行 */
    white-space: nowrap;
    transition: 0.3s;
}
.li:hover ul{
    width: 250px;
}
.li ul li:hover{
    background-image: url("../image/2.jpg");
    background-size: cover;
}
